Internet protocol multicast on passive optical networks

Abstract

A method for implementing multicast via a passive optical network (PON) may include receiving Internet group multicast protocol (IGMP) messages from a customer device. Multicast information associated with the IGMP messages is identified, wherein the multicast information includes at least multicast group information and customer identification information. The multicast information is stored in a multicast state table. Downstream layer 2 traffic is received and multicast addressing information is extracted from the layer 2 traffic. It is then determined whether the multicast addressing information matches the multicast group information stored in the multicast state table. The layer 2 traffic is forwarded on at least one PON interface corresponding to the customer identification information that is associated with the stored multicast group information when the multicast addressing information matches the multicast group information stored in the multicast state table.

Description

BACKGROUND INFORMATION[0001]Internet Protocol (IP) multicast enables modern data networks to save bandwidth and processing capacity by reducing the number of copies of data packets transmitted from a source to a destination. In a traditional unicast model, source devices transmit content (e.g., a video file, etc.) directly to a destination device by referencing an IP address associated with the destination device. Therefore, even if multiple destination devices are requesting the same content at the same time, multiple copies of the content are transmitted simultaneously. While this model is effective for on-demand content-related activity, such as web browsing, it is inefficient for some types of media distributions, such as streaming video for IP television, distance learning, etc.[0002]Multicast operates in a manner more similar to a traditional broadcast model. Destination devices wishing to receive content from a particular source join a multicast group designated by a particul...

AI Technical Summary

Problems solved by technology

While this model is effective for on-demand content-related activity, such as web browsing, it is inefficient for some types of media distributions, such as streaming video for IP television, distance learning, etc.

Unfortunately, implementing IP multicast (IP being a layer 3 protocol) on a layer 2 network, such as the ATM network which forms the basis of many broadband passive optical networks (BPONs), typically requires significant overhead, thereby reducing its effectiveness.

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